Chronotype has been increasingly linked to problematic digital technology use. However, its role among individuals diagnosed with bipolar disorder (BD) is not well studied. This study aimed to examine the association between chronotype and internet, social media, and smartphone addiction in BD patients. The study included 75 BD patients and 50 matched healthy controls (HC). Chronotype was measured using the Morningness - Eveningness Questionnaire (MEQ). Digital addiction was evaluated via the Internet Addiction Test (IAT), Bergen Social Media Addiction Scale (BSMAS), and Nomophobia Questionnaire (NMPQ).The BD group showed significantly higher nomophobia levels compared to the HC group ( = 0.036). Within the BD group, individuals with an evening chronotype had higher IAT and NMPQ scores than their non-evening counterparts ( = 0.008 and = 0.020), although the difference in DIU was not significant ( = 0.302). In the MEQ scores were negatively correlated with IAT in the BD group ( = -0.255, = 0.027), and with all addiction-related measures in the HC group. Covariance analysis indicated that the associations between eveningness and both IAT and NMPQ scores remained significant after controlling for DIU ( = 0.01 and = 0.04) in BD group. Evening chronotype is associated with higher levels of internet addiction and nomophobia, particularly among individuals with BD. Chronotype should be considered a relevant factor in understanding digital addiction patterns in BD patients. p p p p r p p p
